xref: /openbmc/linux/drivers/pnp/driver.c (revision ca79522c)
1 /*
2  * driver.c - device id matching, driver model, etc.
3  *
4  * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
5  */
6 
7 #include <linux/string.h>
8 #include <linux/list.h>
9 #include <linux/module.h>
10 #include <linux/ctype.h>
11 #include <linux/slab.h>
12 #include <linux/pnp.h>
13 #include "base.h"
14 
15 static int compare_func(const char *ida, const char *idb)
16 {
17 	int i;
18 
19 	/* we only need to compare the last 4 chars */
20 	for (i = 3; i < 7; i++) {
21 		if (ida[i] != 'X' &&
22 		    idb[i] != 'X' && toupper(ida[i]) != toupper(idb[i]))
23 			return 0;
24 	}
25 	return 1;
26 }
27 
28 int compare_pnp_id(struct pnp_id *pos, const char *id)
29 {
30 	if (!pos || !id || (strlen(id) != 7))
31 		return 0;
32 	if (memcmp(id, "ANYDEVS", 7) == 0)
33 		return 1;
34 	while (pos) {
35 		if (memcmp(pos->id, id, 3) == 0)
36 			if (compare_func(pos->id, id) == 1)
37 				return 1;
38 		pos = pos->next;
39 	}
40 	return 0;
41 }
42 
43 static const struct pnp_device_id *match_device(struct pnp_driver *drv,
44 						struct pnp_dev *dev)
45 {
46 	const struct pnp_device_id *drv_id = drv->id_table;
47 
48 	if (!drv_id)
49 		return NULL;
50 
51 	while (*drv_id->id) {
52 		if (compare_pnp_id(dev->id, drv_id->id))
53 			return drv_id;
54 		drv_id++;
55 	}
56 	return NULL;
57 }
58 
59 int pnp_device_attach(struct pnp_dev *pnp_dev)
60 {
61 	spin_lock(&pnp_lock);
62 	if (pnp_dev->status != PNP_READY) {
63 		spin_unlock(&pnp_lock);
64 		return -EBUSY;
65 	}
66 	pnp_dev->status = PNP_ATTACHED;
67 	spin_unlock(&pnp_lock);
68 	return 0;
69 }
70 
71 void pnp_device_detach(struct pnp_dev *pnp_dev)
72 {
73 	spin_lock(&pnp_lock);
74 	if (pnp_dev->status == PNP_ATTACHED)
75 		pnp_dev->status = PNP_READY;
76 	spin_unlock(&pnp_lock);
77 	pnp_disable_dev(pnp_dev);
78 }
79 
80 static int pnp_device_probe(struct device *dev)
81 {
82 	int error;
83 	struct pnp_driver *pnp_drv;
84 	struct pnp_dev *pnp_dev;
85 	const struct pnp_device_id *dev_id = NULL;
86 	pnp_dev = to_pnp_dev(dev);
87 	pnp_drv = to_pnp_driver(dev->driver);
88 
89 	error = pnp_device_attach(pnp_dev);
90 	if (error < 0)
91 		return error;
92 
93 	if (pnp_dev->active == 0) {
94 		if (!(pnp_drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE)) {
95 			error = pnp_activate_dev(pnp_dev);
96 			if (error < 0)
97 				return error;
98 		}
99 	} else if ((pnp_drv->flags & PNP_DRIVER_RES_DISABLE)
100 		   == PNP_DRIVER_RES_DISABLE) {
101 		error = pnp_disable_dev(pnp_dev);
102 		if (error < 0)
103 			return error;
104 	}
105 	error = 0;
106 	if (pnp_drv->probe) {
107 		dev_id = match_device(pnp_drv, pnp_dev);
108 		if (dev_id != NULL)
109 			error = pnp_drv->probe(pnp_dev, dev_id);
110 	}
111 	if (error >= 0) {
112 		pnp_dev->driver = pnp_drv;
113 		error = 0;
114 	} else
115 		goto fail;
116 
117 	return error;
118 
119 fail:
120 	pnp_device_detach(pnp_dev);
121 	return error;
122 }
123 
124 static int pnp_device_remove(struct device *dev)
125 {
126 	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
127 	struct pnp_driver *drv = pnp_dev->driver;
128 
129 	if (drv) {
130 		if (drv->remove)
131 			drv->remove(pnp_dev);
132 		pnp_dev->driver = NULL;
133 	}
134 	pnp_device_detach(pnp_dev);
135 	return 0;
136 }
137 
138 static void pnp_device_shutdown(struct device *dev)
139 {
140 	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
141 	struct pnp_driver *drv = pnp_dev->driver;
142 
143 	if (drv && drv->shutdown)
144 		drv->shutdown(pnp_dev);
145 }
146 
147 static int pnp_bus_match(struct device *dev, struct device_driver *drv)
148 {
149 	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
150 	struct pnp_driver *pnp_drv = to_pnp_driver(drv);
151 
152 	if (match_device(pnp_drv, pnp_dev) == NULL)
153 		return 0;
154 	return 1;
155 }
156 
157 static int pnp_bus_suspend(struct device *dev, pm_message_t state)
158 {
159 	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
160 	struct pnp_driver *pnp_drv = pnp_dev->driver;
161 	int error;
162 
163 	if (!pnp_drv)
164 		return 0;
165 
166 	if (pnp_drv->suspend) {
167 		error = pnp_drv->suspend(pnp_dev, state);
168 		if (error)
169 			return error;
170 	}
171 
172 	if (pnp_can_disable(pnp_dev)) {
173 		error = pnp_stop_dev(pnp_dev);
174 		if (error)
175 			return error;
176 	}
177 
178 	if (pnp_dev->protocol->suspend)
179 		pnp_dev->protocol->suspend(pnp_dev, state);
180 	return 0;
181 }
182 
183 static int pnp_bus_resume(struct device *dev)
184 {
185 	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
186 	struct pnp_driver *pnp_drv = pnp_dev->driver;
187 	int error;
188 
189 	if (!pnp_drv)
190 		return 0;
191 
192 	if (pnp_dev->protocol->resume) {
193 		error = pnp_dev->protocol->resume(pnp_dev);
194 		if (error)
195 			return error;
196 	}
197 
198 	if (pnp_can_write(pnp_dev)) {
199 		error = pnp_start_dev(pnp_dev);
200 		if (error)
201 			return error;
202 	}
203 
204 	if (pnp_drv->resume) {
205 		error = pnp_drv->resume(pnp_dev);
206 		if (error)
207 			return error;
208 	}
209 
210 	return 0;
211 }
212 
213 struct bus_type pnp_bus_type = {
214 	.name    = "pnp",
215 	.match   = pnp_bus_match,
216 	.probe   = pnp_device_probe,
217 	.remove  = pnp_device_remove,
218 	.shutdown = pnp_device_shutdown,
219 	.suspend = pnp_bus_suspend,
220 	.resume  = pnp_bus_resume,
221 	.dev_attrs = pnp_interface_attrs,
222 };
223 
224 int pnp_register_driver(struct pnp_driver *drv)
225 {
226 	drv->driver.name = drv->name;
227 	drv->driver.bus = &pnp_bus_type;
228 
229 	return driver_register(&drv->driver);
230 }
231 
232 void pnp_unregister_driver(struct pnp_driver *drv)
233 {
234 	driver_unregister(&drv->driver);
235 }
236 
237 /**
238  * pnp_add_id - adds an EISA id to the specified device
239  * @dev: pointer to the desired device
240  * @id: pointer to an EISA id string
241  */
242 struct pnp_id *pnp_add_id(struct pnp_dev *dev, const char *id)
243 {
244 	struct pnp_id *dev_id, *ptr;
245 
246 	dev_id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
247 	if (!dev_id)
248 		return NULL;
249 
250 	dev_id->id[0] = id[0];
251 	dev_id->id[1] = id[1];
252 	dev_id->id[2] = id[2];
253 	dev_id->id[3] = tolower(id[3]);
254 	dev_id->id[4] = tolower(id[4]);
255 	dev_id->id[5] = tolower(id[5]);
256 	dev_id->id[6] = tolower(id[6]);
257 	dev_id->id[7] = '\0';
258 
259 	dev_id->next = NULL;
260 	ptr = dev->id;
261 	while (ptr && ptr->next)
262 		ptr = ptr->next;
263 	if (ptr)
264 		ptr->next = dev_id;
265 	else
266 		dev->id = dev_id;
267 
268 	return dev_id;
269 }
270 
271 EXPORT_SYMBOL(pnp_register_driver);
272 EXPORT_SYMBOL(pnp_unregister_driver);
273 EXPORT_SYMBOL(pnp_device_attach);
274 EXPORT_SYMBOL(pnp_device_detach);
275